One cryptology scheme is a public key cryptosystem which uses two keys, a public key and a private key that is kept secret. Messages are encrypted using the public key and can only be decrypted using the corresponding private key. For example, a sender encrypts a message with respect to a given public key and only the owner of the private key associated with public key can decrypt the resulting ciphertext and recover the message. Examples of public key cryptosystems include RSA, Digital Signature Standard (DSS), Paillier cryptosystem, and Diffice-Hellman key exchange protocol. Another encryption scheme is a symmetric key cryptosystem that uses a single secure key for encryption and decryption. The secure key is exchanged between parties in a secure initial exchange, and is then used by both parties to encrypt and decrypt messages. Examples of symmetric key cryptosystems include Twofish, Serpent, AES, Blowfish, CAST5, RC4 and IDEA. In addition, hybrid cryptosystems employ both public key cryptosystems and symmetric key cryptosystems. For example, a symmetric key is generated by a sender and encrypted in a message with a recipient's public key. The recipient decrypts the message with its corresponding private key to obtain the symmetric key. The sender and recipient then encrypt and decrypt messages using the symmetric key.
One method to generate cryptographic keys, such as a private key or symmetric key, includes the use of biometric data. However, the use of biometric data can be imprecise and non-repeatable due to the nature of the biometric data collection. For example, an image of a biometric such as a fingerprint or retina may vary depending on the quality of the scanning techniques, movement of the biometric during scanning, background conditions, worn or injured fingertips, etc. In addition, the collection of biometric data raises privacy concerns about the possible unauthorized access and use of the biometric information.
Therefore, a solution is needed that allows use of biometric data for generation of cryptographic keys that is robust and secure.